Unlocking the Power of Enums in Java

The Problem: Case-Sensitivity

Let’s consider an example where we have an enum called TextStyle that represents different styles a block of text can have, such as Bold, Italics, Underline, and Strikethrough. We also have a string variable style that holds the current style we want to apply. The catch? The string isn’t in all-caps.

public enum TextStyle {
    BOLD,
    ITALICS,
    UNDERLINE,
    STRIKETHROUGH
}

The Solution: Using valueOf()

To overcome this hurdle, we can utilize the valueOf() method provided by the enum itself. This method takes a string value as an argument and returns the corresponding enum value.

TextStyle textStyle = TextStyle.valueOf(style);

However, there’s a crucial caveat: valueOf() is case-sensitive. This means that if we pass a string in lowercase or mixed case, it will throw an exception.

The Workaround: toUpperCase() to the Rescue

To avoid this issue, we can simply convert the given string to uppercase using the toUpperCase() method. By doing so, we ensure that the string matches the exact case of the enum values. For instance, if we have an enum value BOLD, we can pass the string “bold” to toUpperCase() to get “BOLD”, which can then be successfully passed to valueOf().

TextStyle textStyle = TextStyle.valueOf(style.toUpperCase());

Avoiding Common Pitfalls

It’s essential to remember that if we don’t use toUpperCase() and instead pass a string with incorrect casing, the program will throw an exception. For example, if we try to pass “bold” directly to valueOf(), we’ll get an error saying No enum constant EnumString.TextStyle.Bold.

• Use toUpperCase() to ensure the correct casing of the string.
• Avoid passing strings with incorrect casing to valueOf().

By following this simple approach, you’ll be able to seamlessly lookup enum values by their string representations, even when the casing doesn’t match.